Overview
Hydrocortisone is a synthetic glucocorticoid that mimics the effects of cortisol, the primary endogenous corticosteroid. It has potent anti-inflammatory, immunosuppressive, and metabolic effects. It is used for replacement therapy in adrenal insufficiency and to treat various inflammatory and autoimmune conditions.
Mechanism of Action
Hydrocortisone binds to intracellular glucocorticoid receptors, forming complexes that translocate to the nucleus and modulate gene transcription. This leads to inhibition of inflammatory mediators (cytokines, chemokines, adhesion molecules), suppression of immune cell function, and regulation of carbohydrate, protein, and lipid metabolism.
Indications
- Adrenal insufficiency (primary and secondary)
- Inflammatory conditions (e.g., rheumatoid arthritis, colitis)
- Allergic disorders
- Dermatological conditions (e.g., eczema, psoriasis)
- Shock (as adjunctive therapy)
- Prevention of organ transplant rejection
Dosage
Dosage varies widely based on indication, severity, and patient response. For adrenal insufficiency: 20-30 mg daily in divided doses (morning and afternoon). For inflammatory conditions: initial dose 20-240 mg daily, tapered to lowest effective dose. Emergency situations (e.g., shock): 100-500 mg IV every 2-6 hours. Always individualize and taper gradually to avoid adrenal crisis.
Contraindications
- Systemic fungal infections (unless for life-threatening conditions)
- Hypersensitivity to hydrocortisone or components
- Live virus vaccinations during immunosuppressive doses
- Idiopathic thrombocytopenic purpura (IM route)
Side Effects
- Insomnia
- Increased appetite, weight gain
- Fluid retention, edema
- Hypertension
- Hyperglycemia
- Mood changes
- Peptic ulcer
- Osteoporosis
- Skin thinning, easy bruising
- Increased infection risk
- Adrenal suppression
- Cataracts, glaucoma
Interactions
- NSAIDs: increased risk of GI ulceration
- Anticoagulants (e.g., warfarin): altered response
- Antidiabetic agents: may require dosage adjustment
- Enzyme inducers (e.g., phenytoin, rifampin): reduced hydrocortisone efficacy
- Potassium-depleting diuretics: enhanced hypokalemia
- Live vaccines: reduced efficacy; avoid during immunosuppression